Art of extracting oil from



Reissued Apr. 24, 1951 ART OF EXTRACTING OIL FROM THE EARTH Ernst Berl,deceased, late of Pittsburgh, Pa., by Walter G. Berl, executor,Pittsburgh, Pa.

No Drawing. Original No. 2,267,548, dated December 2.3, 1941, Serial No.61,804, January 31,

1941, Serial No. 78,890

Matter enclosed in heavy brackets I: Ii appears in the original patentbut forms no part of this reissue specification; matter printed initalics indicates the additions made by reissue.

8 Claims.

The present invention relates to the art of extracting oil from theearth. It has been well known that, heretofore, the extraction of oilfrom the earth has been very incomplete. Tests have demonstrated thatconsiderable quantities of crude oil remained in the mother rock, suchas limestone, sandstone, and the like. In some instances, it has beenfound that about 20% to about 70% of oil remained in the rocks in theearth. The residual oil left in the earth has been considered lost forall practical purposes. Various proposals have been made to avoid thelosses which have been experienced in the past. Of these proposals,mention may be made of the attempts to pump or force water down wellssurrounding the oil well which has been undergoing pumping. In somecases, salt or soda has been added to the water. In a few isolatedcases, some results were obtained, but in most cases the results havebeen unfavorable. None of the attempts [as far as I am aware] as far asit is known has been wholly satisfactory, particularly when carried intopractice on an industrial scale.

[I have] I t has been discovered that the aforesaid losses of oilremaining in the mother rock can be reduced and that considerableimprovements in the yields can be effected from oil wells.

It is an object of the present invention to overcome the unfavorableconditions in the exploitation and recovery of oil from the earth and toutilize an aqueous solution containing substances possessing strongerwetting properties than water for removing oil from the mother rock.

A further object of the present invention is to pump aqueous solutionscontaining wetting agents possessing some solubility in oil into theearth adjacent to the well to release from the mother rock residual oillocked therein.

The invention likewise contemplates the provision of a process ofutilizing capillary active substances to effect the removal ofimprisoned oil and of utilizing aqueous solutions of the aforesaidsubstances containing the so-called polar groups.

Other advantages and objects of the invention will become apparent fromthe following description.

Broadly stated, the invention comprises releasing the oil and freeing itfrom the surrounding rocks to enable the oil to flow together in a massor pool from which it may be removed to the surface of the earth. It hasbeen found that capillarity phenomena cause the adhesion of oil to thesurfaces of the walls of mother rock. By

Application for reissue February 28,

utilizing a watery solution containing an organic oil soluble and watersoluble wetting agent and by pumping this solution into a regioncontaining imprisoned oil, the walls of the rock and even the capillaryspaces are moistened and Wetted by the wetting solutions and the bondbetween the oil and the mother rock is disrupted. It is believed thatthe wetting substance forms a film over the surface of the rock whichenables the oil to form droplets and globules and to collect together ina mass. In this manner, the oil is freed from the mother rock, even thecapillary spaces, and the oil can then be easily separated from the rockand removed from the interior of the earth.

In carrying the present invention into practice, [I have] it has beenfound that aqueous solutions containing wetting substances, especiallycapillary-active substances, are effective to release the imprisoned oilfrom the mother rock and to enable the thus-released oil to run togetherand to be collected and removed from its native environment. [As aresult of extensive experiments, I have discovered that aqueoussolutions containing so-called water-soluble tar acids and/or saltsthereof have given satisfactory results. In addition] [substances]Substances [having similar constitution] containing socalled polargroups, such as OH, NHz, COOH, [SO3H, CSSH] and their combinationsassociated with straight chain hydrocarbons, aromatic ring compounds,etc., etc., are within the purview of the present invention. Thus,satisfactory results have been given by free fatty acids, such as oleicacid, palmitic acid, stearic acid, etc. which contain long carbonchains. [and/or their salts, such as oleates, palmitates, stearates,etc. which are known as soaps] Other examples of oil-- liberating agentsare phenols or aromatic amino compounds, etc., such as aniline and itshomologues, amino phenols, [phenol-sulfonic acids, amido sulfonicacids,] alcohols with long carbon chains, [alcohol sulfonates,xanthogenates] and/or combinations thereof. Aqueous solutions ofsuitable organic dyestuffs may be advantageously used as oil-liberatingagents. For instance, basic dyestuffs, such as crystal violet andmethylene blue, or acid dyestuffs (in weak acid solutions, ifnecessary), such as cloth red and alizarin yellow. [As further examplesof oil-liberating agents, mention may be made of substances used inflotation. A fairly complete list of these flotation agents may be foundin Taggarts Handbook of Ore Dressing (1927 edition, pages 830 to 839).]

In contrast to the foregoing, if water is used in accordance; with. the.priorart teachings in place of the aqueous solutions mentioned herein;been observed that an emulsion of the oil with water formed and that anincomplete removal of the oil occurs.

For the purpose of giving those skilled in the. art a betterunderstanding of. the inventiomthe following illustrative examples aregiven.

[Example No. 1]

[A diluted solution, say about -0.114%.- oftan. alkaline salt, such, forinstancey a sodium -salt of the so-called tar acids may be used as theoil-liberating agent for removal of crude. oil ad.- herin to hydrophilerocks, such as sandstone, limestone; dolomite, etc. The so-ca-lledwatersoluble tar acids may be made, for: instance; according to U. S.Patent No. 1,812,316 or made byadding to 'waterrsoluble taracid oftheacid wash inpetroleum. refining, the alkaline wash liquids: from thepurification of crude oil. tracitions. For the. same purpose, watersolutions of free tar..aci.ds or/and their acid salts, may also be..used, especially infithe. case'of acid. rock like sandstone. In thismanner, a substantially com.- pleteremovaLofthe oil, even in .the finecapil'-. laries may be. effected].

Efcample: No. 1 h

.10 [In contrast to. the foregoing, ifj'water is used inaccordancewithprior art teachings in place, of theaqueoussolutionsmentioned herein, it has been observed'that an emulsion of "theoil? with wateriormedand that anincompleteremoval of the oil'occursJ'fInapplying my solution. ofoileliberating agents... it is, preferred. topump. anaqueous solution containing the same'intothe earthsurroundingthe oilwell through one or. more pipes. For instance, 40 it is preferredto usefour pipes surrounding the oil well, pr.eferably in the fiirmof aquadrangle.

Example No. 2.

Example-"No; 4

Aqueous solution of alkaline salts, of [ethyl or amyl xanthogenates or.alkaline saltsofv higher alcohol sulionates or of. benzol sulfonic acidsor their homologues orlamino phenols [or aromatic aminosulfoniCacidsJQor/and the corresponding,

free. compounds. may beusedfor. thepurpose of.

liberating and removing oil., One may also use for the same purposeaqueous solutions of, amino phenols and amino phenolates, amidocarbonic. acidsor/and their saltsjandmixtures of the substancesmentioned in-this example orinthe fore-.-- goingexamples. Excellentresult haveibeenob tained: by their use.

Example N0. 5

A diluted aqueous solution ofmethylviolet or methylene blue has beenfound to give satisfact'oryresults: for the liberation. and :removal ofoil.

Example No- 6 the:.- following; groups; mam: beeincludediz.

=NH, =S, -SH, CSN-,: and CSNH. [For best results,v sodium salts. of.water. soluble. acid tars and alcohol sulfonates arepreferrecL]-Certain.

advantages may be. obtained in. using suchsubstances which. will. givesoluble calcium salts .becausev thegreatest part off'mother rock whichcontain oil are. formedof limestone or dolomite.

When aqueous. solution of 'a substance. which. produces aninsolublecalciumsaltiare used, capil-- Iariesand fi'nefissures tendftobecomeclogged and certain diflicultiestowardthe liberation and. free fiow ofvoiliare.encountered.

Wli'at'is claimed. is:

1. The processotextracting oil'Ifiomthe earth in regions adjacenttomoth'er rocks, .which comprises introducing. intosuch. regions. [aI'anoil freeing water solutionhaving, no substantial. destructive effectupon saidTmotherv rocks,,said solutz'tm haviiiga wetting eflfectcnsaidbiZ-b'caring. mother rocks, andfcompri's'ing, an organic oil solubleandwater soluble substance containing a polar groupv and free from[sulfonic] "sulfur-containing' acid groups in the molecule.

2; The process of extracting oil'from'the earth in regionsadjacent tomother rocks which comprises introducing into said regions .anoil-freeing wettingagent'comprising, a water solution of an oilsolub'let and water solub'le aromatic compound 2 free from"sulfur-containing acid'groups in the molecule; saidco'mpoun'dbeing amember of the group'consisting'of aniline; amino phenols, aminophenolates; and'phenols: [hand amino carbonic. acids} [3; Theprocess'of' extracting. oil from the earth in regionsadjacentto'motherrocksLwhich comprises intro'ducingdnto'sald regions anoil-freeingagent comprisinga water solution of an arcmatic dyestufi" of"the group consisting. of basic and acid ofjbenzener naphthalene,anthracene andthioanthracene compounds] [4; The'processof extracting oilfrom the earth. inregions adjacent to mother rocks which comprisesintroducing. into. said regions,. an oil-freeing agentcomprisinga watersolution of a salt of a thiocarboxylic acid' having not more than sixcarbon atoms]- 51 Theprocess offemtracting oil. from the earthv inregions adjacent to mother rocks whichcomprises .introducinainto. saidregions. an oilfreeing wetting, agent; comprising a. water solution ataniline.

6. The. process .ojextracting-oil .jrom the earthin.regions.ad7'acent.tomother rocks which comprises. introducing, intosaid regions .an. oil-freeing. wetting ayent comprising a.water solutionof anoil-soluble and'tvater-soluble phenolic compound free fromsulfur-containing acid groups in the molecule.

7. The process of extracting oil from the earth in regions adjacent tomother rocks which comprises introducing into said regions anoil-freeing wetting agent comprising a water solution of an oil-solubleand water-soluble amino phenol compound free from sulfur-containing acidgroups in the molecule.

8. The process of extracting oil from the earth in regions adjacent tomother rocks which comprises introducing into said regions anoil-freeing wetting agent comprising a water solution of an oil-solubleand water-soluble amino phenolate free from sulfur-containing acidgroups in the molecule.

9. The process of claim 1, wherein said substance is an aromaticdyestufi.

10. The process of extracting oil from the earth in regions adjacent tomother rocks which comprises introducing into said regions anoil-freeing wetting agent comprising a water solution of methylene blue.

WALTER G. BERL, Executor of the Last Will and Testament of Ernst Berl,Deceased.

REFERENCES CITED The following references are of record in the file ofthis patent or the original patent:

UNITED STATES PATENTS Number Name Date 1,734,990 Ackerman Nov. 12, 19291,822,271 Goggeshall Sept. 8, 1931 1,823,439 De Groote Sept. 15, 19311,823,440 De Groote Sept. 15, 1931 1,829,705 Walker Oct. 27, 19311,861,176 De Groote May 31, 1932 1,877,504 Grebe et a1 Sept. 13, 19321,894,759 De Groote Jan. 17, 1933 1,911,446 Grebe et al May 30, 19332,024,119 Viette et a1 Dec. 10, 1935 2,024,718 Chamberlain Dec. 17, 19352,032,825 Ambrose Mar. 3, 1936 FOREIGN PATENTS Number Country Date163,519 Great Britain May 26, 1921 OTHER REFERENCES The EiI-ect ofFlooding Oil Sands with Alkaline Solutions, by R. C. Beckstrom and F. M.Van Tuyl, published in American Association of Petroleum GeologistsBulletin, vol. II, January-June, 1927, pages 223-235.

The Separation of Oil Sands by Physical Methods, by Werner Grunder,Chemical Abstracts, vol. 24, pages 5988 and 5989, October-December 1930.

